Name:	brn_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfExpectedLongTermReturnOnAssetsIncreaseDecrease
Namespace Prefix:	brn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The increase (decrease) in pension expense that would occur if the expected return on plan assets was decreased (increased) by 50 basis points.

No definition available.

Name:	brn_DefinedBenefitPlanIncreaseDecreaseFromExpectedReturnOnPlanAssets
Namespace Prefix:	brn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the percentage of ownership interest in affiliated companies required to account investments under equity method investments.

No definition available.

Name:	brn_OwnershipInterestInAffiliatedCompaniesRequiredToAccountInvestmentsUnderEquityMethodInvestments
Namespace Prefix:	brn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

No definition available.

Name:	brn_PrinciplesOfConsolidationAbstract
Namespace Prefix:	brn_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

No definition available.

Name:	srt_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasureAbstract
Namespace Prefix:	srt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Value of input used to measure alternative investment.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

Name:	us-gaap_AlternativeInvestmentMeasurementInput
Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

No definition available.

Name:	us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

No definition available.

Name:	us-gaap_EquityMethodInvestmentsAndJointVenturesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

No definition available.

Name:	us-gaap_NumberOfOperatingSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

No definition available.

Name:	us-gaap_SubsidiaryOrEquityMethodInvesteeCumulativePercentageOwnershipAfterAllTransactions
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Name:	us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	dei_LegalEntityAxis=brn_KaupulehuDevelopmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: